The invention relates to a seal for an antifriction bearing of a tension roller or a deflection roller, which is positioned using a spacer. The seal comprises a sealing cap, which covers an annular gap between an inner bearing ring and an outer bearing ring of the antifriction bearing. The sealing cap rotates with a bearing ring and is spaced axially from the rolling bodies of the antifriction bearing, and is guided while maintaining a sealing gap to the spacer.
German published application DE 41 33 777 A1 shows the construction of a tension roller for a traction drive. The roller-supported tension roller comprises an inner bearing ring, which is arranged on an adjusting bushing in connection with a spacer washer and mounted on the housing, especially the crankcase of an internal combustion engine via a separate attachment bolt. The known tension roller features no measure for connecting the spacer captively to the tensioning device in the preassembled state of the tensioning device. The known seal is unsuitable for vehicles used for off-road driving, which is associated with traveling through water or with a large amount of dirt entering into the installation space provided for the internal combustion engine.
Furthermore, for achieving a defined installation position it is known to provide tension rollers with a spacer, on which preferably the inner ring of the antifriction bearing is positioned. Attachment means, especially a threaded connector, are guided through the longitudinal bore hole of the spacer and the bearing inner ring, in order to fix the structural unit, the tension roller, and also the spacer, for example, to an internal combustion engine. Such spacers have a centering shoulder for holding the inner bearing ring and also a flange, which extends radially over the entire end-side contour of the antifriction bearing. On the outside, the flange, with a cylindrical collar, covers a hub region of a running wheel, which is connected free of rotational play to the outer bearing ring of the antifriction bearing. This known construction requires a securing device for the spacer to the tension roller during the assembly, for example in the form of a separate securing device, which is unnecessary after successful assembly of the tension roller.